**2. Materials and Methods**

The Czech Republic is located in the heart of Europe, bordering Germany, Poland, Slovakia, and Austria. The Czech Republic is divided into 14 regions. The area of interest for the purposes of this paper is the border region of the Moravian-Silesian Region, where the A-CEFs or UA-CEFs under study are located. The Moravian-Silesian Region is situated in the eastern part of the territory of the Czech Republic. The northern and north-eastern part of the region borders Poland (today's border does not correspond with the pre-WWII state border), and the south-eastern part of the region borders Slovakia. The region also borders on the west and south-west with other territorial units—the Olomouc Region and part of the southern border is adjacent to the Zlín Region. The geographical situation of the Moravian-Silesian Region is shown in Figure A1.

Throughout former Czechoslovakia (1918–1938), almost 12,000 CEFs were built (or planned), as well as almost 1000 units of heavy fortifications (artillery logs and forts), which are not the subject of this study [25]. In the Moravian-Silesian region alone (in terms of the current administrative structure of the Czech Republic) 896 CEFs were planned [27]. The continuity of the whole line in the Moravian-Silesian Region is shown in Figure A1. In this figure, there is also a clear continuity with the line in the Olomouc Region. Due to a large number of these objects, only some of them were selected for the purpose of a more detailed study.

Geology and geomorphology played a significant role in the construction of CEFs [35]. It is worth noting that the Moravian-Silesian Region is covered by two geological units, namely the Bohemian Massif and the outer Western Carpathians [43,44]. The development of these two geological units is complemented by quaternary sediments whose origin is linked to continental glaciation, which left deposits of gravels and sands [43,44]. There are all types of relief from highlands and hills to lowlands in the Moravian-Silesian Region [43,44]. As the zoological survey shows, the amount of precipitation and the number of days with snow are crucial. According to Quitt [45], the lowland areas of the Moravian-Silesian Region fall into a moderately warm climatic area, while the mountain and foothill areas fall into a cold climatic area. In relation to the biogeographical classification of the Czech Republic, the territory of the Moravian-Silesian Region is part of the Central European deciduous forest province (like the vast majority territory of the Czech Republic), where parts of three subprovinces meet—the Hercynian subprovince, the Polonian subprovince and the West Carpathian subprovince (simplified in the direction from west to east) [46]. The boundary between the subprovinces is not distinct, and in a large part of the area of interest, it can be characterized as a transitional zone of mutual influence. The fauna here is relatively diverse, which is related to the geographical conditions (mixing of West Carpathian, Polonian, and Hercynian elements) [46].

#### *2.1. Genius Loci—Layer of the Landscape: Searching for Stories of the A-CEFs*

One of the functions of A-CEFs in a post-military landscape is the role they play in specific genius loci [14,47]. In order to capture this potential, a guided interview method was chosen, where respondents were asked about the stories associated with A-CEFs (including capturing the wider context associated with the place). Due to the specific topic of the research, it was necessary to approach suitable respondents who are in some way affected by the genius loci and the associated function of A-CEFs in the landscape. Priority was given to staff from organizations dedicated to leisure activities for children and young people, as well as owners of buildings and last but not least, military history clubs and historians. The initial part of the guided interview dealt with information about the respondent such as age, relationship with WWII history (work/free-time activities/education, etc.), when they first heard about this issue, or if they are visitors/owners of the bunker. As part of the guided interview, respondents were asked two sets of questions with a series of supplementary and extension questions: Q1. Do you know a story associated with A-CEFs (when it happened, where it happened, etc.)? Q2. What do you think about the story (truthfulness, authenticity)? These questions were asked in such a way as to make it clear that the focus of the research is on stories associated with A-CEFs as brownfields and not historical stories (e.g., associated with direct participants in historical events that are associated with A-CEFs serving their original purpose). Respondents were contacted either in person or via electronic communication. Guided interviews were recorded on a dictation machine in the case of in-person interviews. Subsequently, the results of the interviews were transcribed and analyzed.

#### *2.2. Socio-Economic Sphere—Layer of the Landscape: A-CEFs as Brownfields*

For the purpose of our study, the line of A-CEFs (or UA-CEFs) in the Moravian-Silesian Region which stretches from west to east and follows the current northern state border with the Republic of Poland were selected. The entire line of Czechoslovak fortifications (A-CEFs, heavy fortifications, artillery forts) in the Moravian-Silesian region is represented graphically in Figure A1. In this output, the A-CEFs units were marked according to their structural and technical condition (existing—green, destroyed—orange, initiated—purple, obliterated—blue, unbuilt—grey) and are supplemented by heavy fortifications units (red).

This region was chosen because the authors are familiar with the local terrain and because some of the fortifications were among the most completed before the start of WWII. Furthermore, at the end of WWII in 1945, they played an important role during the war between the German and Soviet armies, and after the war, they were not used (the objects on the border with Poland did not become part of the so-called Iron Curtain). They were abandoned and accessed for casual visitors in the frame of the hidden curriculum of the landscape. Due to the large number of existing A-CEFs on the territory of the Moravian-Silesian Region, the selection was made in such a way as to take into account the greatest possible heterogeneity of the selected objects. This includes altitude (highest and lowest positions of the Moravian-Silesian Region, middle positions), location within the Moravian-Silesian Region (the most eastern and the most western), and also the character of the surrounding environment (open, semi-open, and closed exterior environment).

In order to select a suitable sample of fortification units (A-CEFs) for our study, we used data from available historical military maps first depicting the line of fortifications throughout former Czechoslovakia. The original assumption was to divide the line in the territory of today's Moravian-Silesian Region into 10 groups/sections (A-J). Within each group, a selection of 5 existing A-CEFs in different environments (forest/forest edge/arc) were considered. While searching for more detailed information for the selection of the 10 groups, websites of friends of military history were found which contained, among other things, databases with more detailed information—for example, information regarding the technical status. These websites were 'The Interactive Map of Czechoslovak Fortifications 1935–1938 and 'Information on Light Fortifications 1936–1938 [27,36]. A search of these databases revealed that one of the originally intended groups A-CEFs had not been built or the fortifications had been obliterated (this group of buildings was, of course, excluded from the further investigation) Figure A2.

During the field survey, some of the buildings were inaccessible (locked or walled entrances, located on private fenced land, flooded with water, and exceptionally, could not be traced in the field). For these reasons, this methodology has been partially abandoned and the distribution of the surveyed Selected Abandoned Casemates with Enhanced Fortification (SA-CEFs) within the Moravian-Silesian Region results in a less than even distribution. It was possible to include the highest A-CEFs as well as the most eastern and the most western A-CEFs in the SA-CEFs. The selection of 39 SA-CEFs is sufficient for further data analysis and can be suitably supplemented or extended in the future. The distribution of individual SA-CEFs in the Moravian-Silesian Region is shown in Figure A3.

Subsequently, each SA-CEF was categorized according to its geomorphological location (WGS-84), climatic conditions, altitude, administrative section according to the former military administration (original military markings, military section assignment, military numbering), and current ownership. The numbering of individual units does not correspond to the order of data collection but was assigned retrospectively. Within each of the 39 SA-CEFs were in field survey semi-quantitatively detected the orientation of the entrance in relation to cardinal directions, the character of the interior environment (dry/wet/flood), the presence of organic and inorganic material in indoor spaces (none/little/lot), human use (unused/occasionally used/intensively used), accessibility of the entrance were also monitored in each unit (open/semi-open/closed) and the type of exterior environment (open/transitional/closed). The expected output is a graphical representation of the corresponding sections. These 39 SA-CEFs will be further processed not only for brownfields issues but also for the zoological survey.
